In many places around the world, using farmland for solar generation has become a profitable enterprise. Farmers have found that they can often make more money producing electricity instead of food crops. In Japan, where farmland is relatively scarce, this practice was actually prohibited by law.
But now, a new practice known as “Solar Sharing” allows farmers to have their cake and eat it too — or more accurately, to grow crops and harvest solar energy on the same land.
Nearly all plants have a “light saturation point”. After a certain point, additional irradiance does not increase the rate of photosynthesis. So the trick is to design solar panels that allow some, but not all, sunlight to reach crops; the rest is harvested for energy.
This has led to the development of special structures that look much like garden pergolas and support arrays of solar panels that shade less than a third of the area beneath them. The structures provide space for agricultural machinery to move around and are lightweight and easily dismantled.
There are now a number of these solar sharing projects in Japan. The hope is that they can revitalize small farming in the country by providing a way for farmers to increase their income and contribute to both the food supply and the nation’s energy needs. In the US, ranch land is a viable candidate for the same approach.
Dual use of land for wind farms and agriculture is fairly common. With the concept of solar sharing, it appears as if solar energy can also coexist with farming.
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Japan Next-Generation Farmers Cultivate Crops and Solar Energy
Photo, taken on September 28, 2008, courtesy of Till Westermayer via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio. Support for Earth Wise comes from the Cary Institute of Ecosystem Studies in Millbrook, NY.